If You Can't Buy 'Em Make 'Em - The Saga Continues

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Manage to get a makeshift mandrel and did a quick flare for the funnel standpipe. Its not pretty and this the best I could achieve for now.
Side by side comparison to the one that I presently use. I tried to get the inlet as wide as possible.
Almost there, but the tapper is shallow and over a longer neck distance as compared to the ready made adapter.
I use this wooded stick above that available in local hardware for use with gardening tools as a mandrel. I need to make the tapped part more so that it will create a shorter transition from the bigger diameter to the smaller. Where is a Tobasco bottle when I needed one.
I use hair dryer to heat up the PVC pipe and gently press it against the mandrel. Constant reheating required to prevent PVC harden. A slow process, I don't have a heat gun other wise it could be much quicker. Heat produce by a hair dryer isn't industrial strength, but it does work.
Above the 25/20 adapter standpipe and below the home made flared standpipe. It remind me of trumpet and I need to make it wider, for now its okay.
Below is the water inflow where it start to flush.
This next picture below, water inflow that it will be able to stop.
Starting water is less that the stopping water, this will make it possible for make it operates somewhere in between these two inflow. A short test shows that the water inflow it able to stop is about 2x the minimum siphon starting inflow water. This is a good indication that it may be able to work.
I suspect the longer neck of this trumpet making transition very gradual lessen its effectiveness. I must try to make it broader and shorter neck as illustrate above.

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  1. Never thoutht to make one, thanks for the tip. Love your blog. thanks again.

  2. Thanks LOU, I am still testing this, so far all looks good.

  3. I've been joining same sized PVC pipes using this technique. But I normally use the kitchen gas stove. Hover over your pipe end to be soften while rotating about 3 inches above the flame. Once you get the desired softness, press in the joining pipe to the required lapping length, making sure everything is straight. Once satisfied, dip in cold water. You'll get a perfect airtight join, and if needed you can glue it later.

  4. @acanov, this is how normally we do the joints. I am trying not to go that path yet until I get the correct size wooden mandrel made.

    Looks like I may have no choice and use this method, since the hair dryer don't produce enough heat.

  5. You should make the mandrel out of steel. A local engineering shop or a motor mechanic with a lathe could make one up in no time. The benefit of steel is that you can pre-heat it and that will stop the plastic from cooling down while it is being molded.

  6. Very true Doug, I try the home made approach first. This way if I could do it then every one will be able too. That's the only reason why I choose the low tech way.

    Having mandrel made from steel, may not be everyone option.

  7. Could you use a 1 1/4" coupler with a 1 1/4 > 3/4" bushing? And add silicone to form the angled "lip" -- create your funnel?

    Would mimic the flare you are aiming for without having to use the hair dryer and mandrel?

    Just a thought...

    1. That will do,but will the silicone stays.